The invention relates to conveyors for positioning articles, and more particularly relates to a conveyor system for positioning meat patties from a feed conveyor onto a downstream conveyor.
Conveyor systems are known which include a feed conveyor arranged to receive a stream of meat patties from a meat patty-forming machine in a grid pattern having a first width, and which deposit the stream onto a downstream conveyor that is arranged below and at a right angle to the feed conveyor. The downstream conveyor has a wider width and a slower operating speed. The downstream conveyor is typically used for treating the patties, such as for conveying the patties through a thermal treating unit, either a heating or a cooling unit.
The feed conveyor is controllably extendable and retractable to distribute the stream in a longitudinal direction onto the downstream conveyor, in the lateral direction across a width of the downstream conveyor. The feed conveyor includes a wire mesh conveyor belt having a belt accumulation arrangement located beneath the top surface of the conveyor.
The amount of belt storage, and effectively, the length of the top conveying surface, of the feed conveyor are controlled by movement of a carriage. The carriage carries an idler roller or pulley that is wrapped by the belt. The carriage is moved by a pneumatically controlled cylinder. The conveyor system is operated using pneumatic controls. The carriage retract distance is set by a limit switch. The carriage retraction speed and advancement speed are controlled by pneumatic flow control. The retraction of the carriage is initiated by an electric photo-eye. The conveyor belt circulating speed is controlled by variable speed pulleys.
Although the aforementioned system operates effectively, the present inventors have recognized the desirability of providing a system that is more easily adjusted and controlled, and can be more cost effectively manufactured, and which can be more efficiently and effectively operated.
The invention provides a feed conveyor for depositing articles onto a downstream conveyor, comprising: an endless circulating belt having an upper conveying surface; a roller controlling a belt accumulation region of the endless circulating belt, the conveying surface having an upstream region adapted to receive a stream of articles in rows across a lateral direction of the belt, the belt circulated to move the rows in the longitudinal direction to an end of the conveying surface, wherein the endless belt is turned over at the end, wherein circulation of the belt passes the rows off of the conveying surface to be deposited onto the downstream conveyor, and the longitudinal position of the end is movable between an extended position and a retracted position passing across at least a portion of a transverse dimension of the downstream conveyor by longitudinal positioning of the roller; a first electric motor and a traction device, the traction device engaged to be translated by the first electric motor, the roller mechanically connected to the traction device to be moved longitudinally thereby; a second electric motor, wherein the conveying surface is circulated by mechanical communication from the second electric motor; and a controller operationally connected to the first and second electric motors to precisely control the conveying speed of the conveying surface and the position of the end.
The invention also provides a system for depositing patties onto a downstream conveyor, comprising: a patty-forming machine having a reciprocating mold plate and a mechanism to eject patties from the reciprocating mold plate; a feed conveyor having an endless circulating belt with an upper conveying surface and a roller controlling a belt accumulation region of the endless circulating belt, the conveying surface having an upstream region adapted to receive a stream of patties from the patty-forming machine in rows across a lateral direction of the belt, the belt circulated to move the rows in the longitudinal direction to an end of the conveying surface, wherein the endless belt is turned over at the end, wherein circulation of the belt passes the rows off of the conveying surface to be deposited onto the downstream conveyor, and the longitudinal position of the end is movable between an extended position and a retracted position passing across at least a portion of a transverse dimension of the downstream conveyor by longitudinal positioning of the roller; a first electric motor and a traction device, the traction device engaged to be translated by the first electric motor, the roller mechanically connected to the traction device to be moved longitudinally thereby; a second electric motor, wherein the conveying surface is circulated by mechanical communication from the second electric motor; and a controller operationally connected to the first and second electric motors to precisely control the conveying speed of the conveying surface and the position of the end.
According to an exemplary embodiment, the present invention provides a feed conveyor operable in a first direction to deposit a stream of articles across a width of a downstream conveyor operating along a second direction, the second direction being at an angle to the first direction. The feed conveyor is an extendable conveyor that is accurately controlled for circulating speed, extension speed and retraction speed, to deposit articles transversely onto the downstream conveyor in a tightly spaced, grid pattern. The conveying speed of the feed conveyor is controlled by a first servomotor, and the extension and retraction speed are controlled by a second servomotor.
The feed conveyor includes a wire mesh conveyor belt having a belt accumulation arrangement located beneath the top surface of the conveyor.
The amount of belt storage, and effectively, the length of the top conveying surface, of the feed conveyor are controlled by movement of a carriage. The carriage carries an idler roller or pulley that is wrapped by the belt.
The feed conveyor is driven to convey at a precise speed by the servomotor. The carriage is connected to an endless belt drive that is precisely driven by the servomotor in both the extension and retraction directions.
According to the invention, a controller acts as an operator interface and as an automatic control. The desired extension and retraction distance is set by a keypad entry. The articles size is also set by a keypad entry. The speed of the articles entering the feed conveyor is input automatically. The home position of the carriage, the fully extended position of the feed conveyor, is input by a proximity sensor. The controller calculates the optimal article spacing using the retraction distance and the article size multiplied by a maximum whole number of articles to be spaced transversely across the downstream conveyor. The controller operates the servo controls such that carriage advancement or retraction speed, carriage advancement and retraction acceleration and deceleration, and carriage stroke, are all closely controlled. The carriage belt speed is closely controlled to match the input speed of articles fed onto the feed conveyor. The carriage retraction initiation is also controlled by the controller.
The present invention is particularly advantageous as applied to meat patties formed by a meat patty-forming machine such as a FORMAX F-26 machine available from Formax, Inc. of Mokena, Ill. and/or as described in U.S. Pat. Nos. 4,182,003 and 4,821,376, and/or PCT WO99/62344.
The patties are formed by the patty-forming machine and deposited onto the feed conveyor. The feed conveyor includes a circulating wire mesh belt that delivers a grid pattern stream of formed patties to an end of the conveyor wherein the patties are deposited row by row onto the downstream conveyor as the conveying surface of the feed conveyor is retracted across a width of the downstream conveyor. Both the feed conveyor and the downstream conveyor are continuously circulating. The patties deposited on the downstream conveyor are actually deposited in a slight angular grid pattern due to the continuous movement of the downstream conveyor during deposition of the patties thereon.
The circulating speed of the feed conveyor is servo controlled to match the patty output of the forming machine. A proximity sensor acts to sense the reciprocation of the mold plate of the forming machine to adjust the speed of the feed conveyor to achieve a closely-spaced, non-overlapping, continuously grid pattern of patties on the feed conveyor. The advancing speed of the end of the feed conveyor is closely controlled to be about equal to the circulating speed of the conveyor, and the retracting speed is closely controlled to precisely deposit rows of patties in a closely spaced grid positioning on the downstream conveyor.
Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims, and from the accompanying drawings.